Session 1

10:00 - 12:30

Netherlands III

Radiation Dose Reduction Strategy and its Application as Low-dose CT in Future
10:00 Prof. Hajo Zeeb, Institute for Epidemiology and Prevention Research BIPS

“Basics and Overview of Medical Radiation Doses”
10:35 Prof. Yoshiharu Ohno, Kobe University“Radiation Dose Management and Dose Reduction Strategy in Clinical Practice”
11:10 Dr. Wolfram Stiller, University Hospital Heidelberg“Low-dose CT and Computer-aided Diagnosis in the Abdominal Field”
11:45 Assoc. Prof. Sumiaki Matsumoto, Kobe University“Low-dose CT and Computer-aided Diagnosis in Chest Field”
12:20 Discussion“The 3rd Kobe University Brussels European Centre Symposium” was held at Thon Hotel EU in Brussels on December 6, 2012. In thissymposium, we have a session entitled “Radiation Dose Reduction Strategy and its Application as Low-dose CT in Future”. In this session,
four speakers have lectures, and discuss with audiences from EU.
The ﬁrst speaker is Prof. Dr.med. Hajo Zeeb, MSc from Bremen Institute for Prevention Research and Social Medicine (BIPS). He had alecture entitled “Basics and Overview of Medical Radiation Doses”, and present importance of radiation dose reduction, the current situation of radiation dose issue in medical ﬁeld, and necessity for radiation dose reduction for public health. The second speaker is me, Prof.
Yoshiharu Ohno, M.D., Ph.D. from Kobe University. I had a lecture entitled “Radiation Dose Management and Dose Reduction Strategy inClinical Practice”, and present state of the art CT radiation dose reduction strategy, recently developed reconstruction technique for further
radiation dose reduction, and its’ application in chest CT imaging. The third speaker is Assistant Prof. Dr. Wolfram Stiller, Diplom-Physikerfrom Heidelberg University. He had a lecture entitled “Low-dose CT and Computer-aided Diagnosis in the Abdominal Field”, and present
state of the art CT radiation dose reduction strategies, recently developed CT reconstruction technique for further radiation dose reduction,and its’ application in abdominal CT imaging. The ﬁnal speaker is Associate Prof. Sumiaki Matsumoto, M.D., Ph.D. from Kobe University.
He had a lecture entitled “Low-dose CT and Computer-aided Diagnosis in Chest Field”, and present state of the art computer-aided diagnosis (CAD) and inﬂuence of state of the art CT radiation dose reduction technique to CAD in chest CT imaging.
We hope this symposium will contribute future collaborations between Kobe University and EU institution, and obtain fruitful results in nearfuture.

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Technical developments in CT scanners have enabledProf. Hajo Zeeblarger volume coverage with higher resolution and lower

Institute for Epidemiology and Prevention Research
BIPS, Bremen, Germany

noise, but this has led to increased radiation exposure.
Previous studies in the United States, United Kingdom,
Germany, and Japan have shown approximately twofold
increases in the number of CT examinations performed“Basics and Overview of Medical Radiation
Doses”in the last a few decades. Currently, the issue of radia-

Modern medicine contributes atice varies among institutions, which illustrates the lackmajor share to the overall radia-of a standard protocol for effectively reducing radiation

tion dose of the population, anddose to patients in clinical settings.

this share has been increasing inTo show the available data on reducing radiation dosethe past decades. Even if most

exposure in routine chest and abdominal CT protocols,

radiological investigations are jus-

I will introduce 1) important techniques and factors fol-tified and contribute to the healthlowed by a review of previous studies of CT radiationof patients, there is a need to aim

dose reduction, 2) results from our international andfor the lowest possible doses while maintaining or evendomestic multi-center studies, 3) newly developed tech-improving the quality of radiological images. Computer-niques and 4) future applications for CT developing at

ized tomography is of major interest in this regard as it

Advanced Biomedical Imaging Research Center in Kobe

delivers radiation doses to the patients that are muchUniversity.

tion dose reduction draws wide attention. However, application of reduced-dose CT techniques in clinical prac-higher than conventional X-ray in many cases. The presentation looks at the current international trends in medical radiation doses and provides some insight into new
epidemiological data on potential long-term risks associated with medical diagnostic imaging, predominantly
computerized tomography.

1, 2

Yoshiharu Ohno, M.D., Ph.D.
1

Advanced Biomedical Imaging Research Center,
Kobe University Graduate School of Medicine,
Kobe, Hyogo, Japan
2
Division of Functional and Diagnostic Imaging
Research, Department of Radiology, Kobe
University Graduate School of Medicine, Kobe,Hyogo, JapanDr. Wolfram Stiller, Dipl.-Phys.

Department of Diagnostic and Interventional
Radiology, University Hospital Heidelberg“Low-dose CT and Computer-aided
Diagnosis in the Abdominal Field”
The contribution of CT examinations to collective effective
dose caused by all diagnostic
procedures involving patients’
exposure to ionizing radiation isever increasing, leading to highinterest in its reduction. With regard to radiation dose reduction,“Radiation Dose Management and Dose
Reduction Strategy in Clinical Practice”

abdominal CT examinations pose a challenge inasmuch

CT is a powerful tool for the ex-their differentiation difficult, while ionizing radiation isamination of chest and abdominal

highly absorbed by the dense structures located in thisdiseases because it can depict

body region. Therefore abdominal CT examinations are

the disease process far morenormally associated with rather high doses. However,clearly than chest or abdominal

low-dose abdominal CT is still feasible and applicableradiographs, and more information

for clinical conditions which imply an increase in con-than conventional angiography.

trast of abdominal anatomy either artificially by usingas the organs and structures of the abdominal region
feature inherently low differences in contrast rendering

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contrast-enhanced CT for imaging vascular structures or

any non-calcified lung nodule may be a manifestation of

the intestines, or for lesions with inherent high-contrast

lung cancer but can be overlooked by radiologists and it

like renal concrements or metastatic skeletal invasions.

is impossible for radiologists to quantitatively assess theApart from these applications new iterative image recon-extent of emphysema without the use of image process-struction techniques enable abdominal CT imaging ating. This lecture focuses on our approach to computer-lower doses while preserving diagnostic quality and con-aided detection of lung nodules and quantitative assess-fidence. Since the amount of image data generated byment of emphysema, in the contexts of global attention

CT examinations is very large and requires scrutinous

to lung cancer screening using low-dose CT and thereview, computer-assistance for supporting radiologicalrecent trend towards radiation dose reduction using new

diagnosis and clinical decisions could prove to be valu-

iterative reconstruction algorithms.

able. To date, approaches to computer-aided diagnosis
on the basis of abdominal CT imaging include the automatic identification of colorectal lesions in virtual coloscopy as well as the automatic segmentation of hepaticlesions or of the liver’s vascular system.

Sumiaki Matsumoto, M.D., Ph.D.1, 2
1Advanced Biomedical Imaging Research Center,
Kobe University Graduate School of Medicine,
Kobe, Hyogo, Japan
2
Division of Functional and Diagnostic Imaging
Research, Department of Radiology, Kobe
University Graduate School of Medicine, Kobe,
Hyogo, Japan“Low-dose CT and Computer-aided
Diagnosis in Chest Field”
Over the last two decades, thetechnology of CT (computedtomography) has made great
improvements. Recent multidetector-row CT scanners offer
remarkable speed of scanning,spatial resolution, and anatomic
coverage, allowing for quick acquisition of high-quality 3D CT data of a body part oreven the whole body. And nowadays such 3D data canbe processed by specialized computer systems aimed
for computer-aided diagnosis. Computer-aided diagnosis in radiology can be defined as a diagnosis made bya radiologist who uses the output from a computerized
analysis of medical images as a “second opinion” in detecting lesions, assessing extent of disease, and making
diagnostic decisions. In the sub-field of chest radiology,
lung nodules and pulmonary emphysema constitute important targets for computer-aided diagnosis, because

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